• Journal of fish pathology
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• v.25 no.2
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• pp.103-109
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• 2012

The objective of this study was to investigate the effects of exposured $Cu^{2+}$ on growth and bioaccumulation of abalone Haliotis discus hannai. Abalone were exposed to various concentration of $Cu^{2+}$ (0, 5, 10, 20, $40{\mu}g/L$). Bioaccumulation of tissues, hepatopancreas, muscles and gills were measured. hepatopancreas and gills $Cu^{2+}$ concentration of abalone increases to extent during the 4 weeks accumulation time. But muscles showed no significant changes, with respect to control. These data indicate that abalone Haliotis discus hannai hepatopancreas and gills can be considered adequate target tissues for waterborne exposured of $Cu^{2+}$. Weight growth rate of abalone exposed to $Cu^{2+}$ was significantly decreased in 20 and $40{\mu}g/L$ groups compared to control. This study revealed that high $Cu^{2+}$ concentration (${\geq}20{\mu}g/{\ell}$) reduced growth of abalone. These data indicate that excessive waterborne $Cu^{2+}$ can affect the toxicity of xenbiotics to abalone through alterations in growth rate. Thus, environmental standard of $Cu^{2+}$ $20{\mu}g/L$, should be considered a potential source of variation in toxicological studies with abalone.

• The Journal of Fisheries Business Administration
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• v.44 no.3
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• pp.15-28
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• 2013

Abalone aquaculture has developed very rapidly in Korea. Until the mid 1990s it has annually produced about 100 tons. Since then the yield has increased to about 9,000 tons in 2012. The amount accounts for 20% of the global abalone yield. About 86% of produced abalone is consumed domestically and the rest is exported. 100 tons for export seemed as an unattainable goal back in 2003. However, the export rose up to 1,333 tons in 2012. Despite its rapid growth, Korean abalone industry is faced with some problems. The first is the slowdown of yield increase rates. Abalone production increased by 50~60% until the mid 2000. However, the rate continued to drop to below 10%. Reasons behind the slow increase are deteriorating aquaculture grounds and worsening market problems. Constant aquaculture aggravated productivity and overcrowded facilities at a limited space made matters worse. Moreover, abalone export has stalled and so did domestic consumption. In the meantime, rising mortality of young abalone has lowered productivity at abalone breeding places. The mortality rates of abalone remained below 5% in the early 2000s but rose to 30~40% these days. This translates into rising abalone prices. The market problems imply stagnant or shrinking export as well as domestic consumption. The export increase rates took a nosedive from 200 to below 50 between the early 2000s and the late 2000s. Moreover, the increase rates of domestic consumption have become remarkably sluggish. According to, it stood at 50~60% in the mid 2000s but continued to decrease after 2008. These problems, in turn, affected the size of abalone. The usual abalone size for market was 10~12 shells per kg, but recently the size became smaller and smaller to 15~16 shells per kg. The change of size implies shift in consumption patterns: Consumers not only eat live abalone but also they cook soup with it. The size of abalone for uncooked dish is usually very big, like 10~12 shells per kg. In contrast, smaller abalone, such as 20~25 shells per kg, are used for making soup. Increasing use of smaller abalone leads to lower income of abalone aquaculture households. This is partly because that the size determines the price and the price gap between big abalones and smaller ones is extreme in Korea. For the sustainable growth of Korean abalone industry, we need to come up with strategies. First, a reasonable production system needs to be in place, especially for better management of abalone aquaculture grounds. Management of abalone licenses is also necessary because local governments issue relevant licenses as well as supervising abalone grounds. Second, abalone export destination need to be diversified. Japan, the major importer of Korean abalone, takes up a lion's share of export, at 95%. Third, new consumption style of abalone needs to be developed. Abalone used to be consumed as 'raw type' or Sashimi in Korea. This sole type of consumption hampers the growth of abalone market. Moreover, more strategies are needed to encourage and distribute home cooking of abalone rather than eating-out at restaurants. Last but not least, distribution system should be improved for better delivery of live abalone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.2
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• pp.154-159
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• 2014

The increasing of atmospheric $CO_2$ are changing the pH (ocean acidification) and temperature of the sea. Although the effects of ocean acidification on calcifying organisms have well-documented, only a few studies have examined the combined effects of ocean acidification and elevated temperature. This study investigated the effects of ocean acidification and elevated temperature for 2100 on survival and growth of juvenile abalone, Haliotis discus hannai. Ocean acidification was simulated by bubbling $CO_2$ into seawater at concentrations of 1,000 and 1,500 ppm, and temperature was set at room temperature $+2^{\circ}C$. Neither $CO_2$ nor temperature had a significant effect on survival of abalone, while both significantly affected growth. There was no significant interaction between the two factors. Shell length can be used as a growth index of abalone to access the impacts of ocean acidification and elevated temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.601-605
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• 2003

This study investigated the effect of dietary pigment sources on growth and shell color of juvenile abalone(Haliotis discus hannai). Three replicate groups of the abalone (average weight 173 mg) were fed diets containing various pigment sources such as Porphyra powder, Spirulina, yeast astaxanthin, and paprika extract for 16 weeks. Survival and weight gain were not affected by dietary pigment sources (P>0.05). Shell color of abalone fed diets containing Porphyra powder and Spirulina approached the yellow-red and orange, colors similar to wild abalone. However, shell color of abalone fed the diets containing yeast astaxanthin and paprika extract were similar to the bright green control group. These results should be useful for changing the shell color of abalone in aquaculture.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.6
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• pp.586-590
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• 2003

The effect of water temperature and feed on the growth, survival, and body composition of juvenile abalone (Haliotis discus hannai) fed an artificial formulated diet and a macroalgae (Laminaria japonica) for 12 weeks was investigated. Rearing temperature was maintained at $13{\circ}C,\;16{\circ}C,\;19{\circ}C$ by heated and natural sea water temperatures $(7.5-10.2{\circ}C).$ Shell growth, weight gain, and survival rate of the abalone were affected by water temperature and diet (P<0.05). Survival and growth rate of the abalone fed with the formulated diet and Laminaria at $19{\circ}C$ was significantly higher than those of the abalone fed the formulated diet or Laminaria at $13{\circ}C,\;16{\circ}C,$ and ambient temperatures (P<0.05). Moisture, crude protein, crude lipid, and ash contents of the soft whole body were affected mainly by diet than rearing water temperature (P<0.05). These indicate that a mixture of formulated diet and macroalgae could improve the growth of the abalone independent of water temperature and heated water could improve the growth of abalone during the winter season.

• Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.159-164
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• 2015

A feeding experiment was conducted to determine the effect of dietary distillers dried grain (DDG) on the growth and body composition of juvenile abalone, Haliotis discus hannai. Three diets were formulated to contain 0% (DDG0), 30% DDG (DDG1) replacing wheat flour and 30% DDG (DDG2) replacing fish meal and wheat flour. A commercial feed (CF) was also compared with experimental diets. Three replicate groups of abalone averaging $0.6{\pm}0.01g$ were fed one of the four diets for 14 weeks. The highest survival rate was observed in the abalone fed the DDG2 diet, which was higher than that of abalone fed the DDG0 diet. Weight gain, shell length, shell width and soft body weight of the abalone were not affected by dietary DDG and CF diet (P > 0.05). Proximate and amino acid composition of the soft whole body were not affected by dietary DDG and CF diet (P > 0.05). The result of this experiment suggests that DDG is a good ingredient to replace fish meal and wheat flour in the diet and could be used up to 30% in the diet without negative effects on the growth performance of juvenile abalone Haliotis discus hannai.

• The Korean Journal of Malacology
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• v.28 no.4
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• pp.343-347
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• 2012

The growth rates of offspring of selected abalone (SA), Haliotis discus hannai, population for rapid growth were compared to those of offsping of the control abalone (CA) at bred under the same condition. The growth traits (shell length, shell breadth and total weight) of SA were significantly faster than those of CA at this experiment. At the 45th day and 90th day, the growth rates in shell length of SA were estimated 31.7% and 17.8% faster than those of CA, total weight of SA were estimated 43.7% and 25.6%, respectively. Moreover, the relative growth rate between shell length and total weight of SA showed significant differences higher than one in CA at 90th day. The results suggest a possibility of improving the growth rate of cultured abalone using selection techniques.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.6
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• pp.738-744
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• 2017

Effect of dietary inclusion of microalgae, diatom-dominant, oil extracts (MOE) on growth, body composition and shell color of juvenile abalone Haliotis discus was investigated. One thousand four hundred and seventy juvenile abalone were distributed into 21 plastic rectangular containers. Seven experimental diets were prepared: MOE0, MOE0.01, MOE0.05, MOE0.1, MOE0.5, MOE1 and MOE2 diets containing MOE at the concentrations of 0, 0.01, 0.05, 0.1, 0.5, 1 and 2% at the expense of mixture of squid liver and soybean oils, respectively. The experimental diets were fed to abalone in triplicate once a day with a little leftover for 16 weeks. Weight gain and specific growth rate of abalone fed the MOE1 and MOE2 diets were higher than those of abalone fed the all other diets. The shell length and soft body weight of abalone fed the MOE2 diet were longer and heavier than those of abalone fed the all other diets. Crude protein and ash content of the soft body of abalone were affected by dietary inclusion of MOE. The shell color of abalone fed the all experimental diets was different from that of wild abalone. In conclusion, dietary inclusion of MOE improved growth of abalone, but did not shell color of abalone.

• Fisheries and Aquatic Sciences
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• v.24 no.3
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• pp.129-137
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• 2021

Dietary protein requirements of abalone (Haliotis discus) depending on abalone size were determined and compared. One thousand and fifty small abalone (initial weight of 2.7 g) and five hundred forty large one (initial weight of 16.0 g) were distributed into 15 and 18 containers in Trial 1 and 2, respectively. Five and six experimental diets containing crude protein level from 20% to 40% and 20% to 45% with 5% increment of protein level for the small and large abalone were prepared and referred to as the CP20, CP25, CP30, CP35, CP40, and CP45 diets, respectively. The experimental diets were fed to abalone for 16 weeks in Trials 1 and 2. Specific growth rate (SGR) of the small abalone fed the CP20 diet was lower compared to that of abalone fed all other diets in Trial 1. Growth performance (weight gain and SGR) of the large abalone fed the CP30, CP35, and CP40 diets were greater than that of abalone fed the CP20, CP25, and CP45 diets in Trial 2. Dietary protein requirements were estimated to be 33.0% and 33.5% for the small and large abalone based on the 2^nd order polynomial analysis, respectively. Dietary protein requirements for the small abalone grown from 2.7 g to 7.4 g and the large one grown from 16 g to 21 g were estimated to be 33.0% and 33.5%, respectively. Size differences in abalone did not affect dietary protein requirement under this experimental conditions.

• Journal of fish pathology
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• v.28 no.1
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• pp.53-62
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• 2015

Here, we report the physiological changes and growth in disk abalone, Haliotis discus discus, in relation to dietary supplementation with citrus pomace (CP) 6%, Ecklonia cava residue (ECR) 6%, and CP + ECR (3% + 3%). The composition and nutrient content, survival rate and growth rate were measured 0, 4, 8 and 12 weeks after feeding the supplemented diets of CP and/or ECR. Moreover, the experiment of low salinity stress (25psu) for environmental resistance was examined for a period of 48 hours after feeding the supplemented diets for 12 weeks. The activities of superoxide dismutase (SOD), catalase (CAT), lysozymes, respiratory burst, and phenoloxidase were measured. The moisture content and crude protein condition of the body were increased with the addition of ECR only (P<0.05). We observed higher levels of survival in the experimental group compared with the control group. Moreover, the growth disk abalone that were fed a diet containing ECR was higher compared with the control group. However, the growth of abalone fed a diet containing CP was similar to the control group. With a rearing condition of low salinity stress, survival rate and lysozyme activity were increased in the ECR group compared with the control group. Dietary ECR reduced the level of CAT activity to approximately 30% of the control, however the level of CAT activity in the ECR group was similar to the start level of the previous stress. These results suggest that dietary ECR gives rise to an enhanced immunity in disk abalone, as a result of the decrease in CAT and lysozyme activity in particular. Accordingly, the growth and survival rate were increased by feeding an ECR-supplemented diet in the rearing of disk abalone, Haliotis discus discus.